The invention provides a system and method for detecting current harmonics of a photovoltaic inverter. The system and method are characterized in that the system is provided with a PC, a power analyzer, the detected photovoltaic inverter and a data converter; the power analyzer uploads acquired current harmonic data in the detected photovoltaic inverter to the PC, the current harmonic data are stored through a current harmonic detected data capture function module and a calculation function module which are embedded into the PC and guided in an Excel form to be processed, and finally a report form is generated and printed. The method is easy and convenient to implement, detection reliability is improved, and detection time is shortened.